I'd recommend 'Grammar for english language teachers' by Martin Parrot. Even if you're never ever going to teach english the book has everything and the explanations are really good.

Yes, it is. I'd certainly recommend it. Many language learners and schools describe the English Grammar in Use series as 'their bible'. It has been Cambridge University Press's best-selling series of books for decades, and rightly so. 

Thank you! I'll definitely give it a try.

You need structure to learn grammar, don't you?

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